Mud degassers



MUD DEGASSERS 2 Sheets-Sheet l Q c 0 V 0 D 0 0 v IN VENTORS PHIL H.GRIFFIN, 111 JOHN W. MELTON,JR.

ATTORNEY" P. H. GRIFFIN III, ETAL Jan. 16, 1968 Filed Oct. 6, 1964 {Ifm. I I I I lI IHHHHHI H I HHHI IIHHHIIIJJ I I I mm .8 i IIIIIIII-IIIII\.II\III mw fii ML m- A mvmo m @N H mm g \t mm 4 Jan- 16, 196 P. H.GRIFFIQN m, ETAL 3,

MUD DEGAS SEES 2 Sheets-Sheet 2 Filed Oct. 6, 1964 Mud level fdlling-Vacuum increased 22 v Z INVENTORS d e S 0 G 8 .mu 5 e ."d m V U M C 0 Vu M u H 7 3 a m e x 3 K a ATTORNEY United States Patent 3 Claims. (Cl.55-170) ABSTRACT OF THE DISCLOSURE The present application disclosesdrilling mud degassing apparatus, the combination of a horizontallyelongated vacuum tank having an inlet end and an outlet end, an intakepipe for gas cut mud extending into the inlet end of said tank, anoutlet pipe for gas free mud extending from the bot-tom portion of thetank outwardly through the outlet end thereof for recirculation of gasfree mud to a well, a vacuum pump, a suction line extending from saidpump, a three-way vacuum control valve having a first port connected tosaid suction line, a second port, and port means communicating with theatmosphere, a suction pipe extending from said second port of said valveto the interior of said tank, a float buoyant on the level of mud in thebottom portion of the tank, and means operatively connecting said floatto said control valve whereby the valve may directly communicate saidsuction pipe to said suction line and pump to increase the vacuum in thetank when the mud level is falling and whereby the valve may communicatesaid suction pipe through said port means with the atmosphere todecrease the vacuum in the tank when the mud level rises.

The present application is a continuation-in-part of our applicationSer. No. 308,314, now Patent No. 3,241,295, dated Mar. 22, 1966, whichapplication is a continuationin-part of our application Ser. No. 37,685,filed June 21, 1960, now abandoned.

This invention relates to new and useful improvements in drilling mudde-gassers for oil wells, and the principal object of the invention isto facilitate simple and highly efficient removal'of gas from gas cutmud for recirculation of gas free mud to the well.

In accordance with the invention, gas cut mud is passed into ahorizontally elongated vacuum tank, such as shown in Erwin Patents Nos.2,748,884 and 2,869,673 where it is permitted to cascade over baflleplates, the vacuum in the tank eflectively withdrawing all gases fromthe mud and the gas free mud collecting in the bottom of the tank fromwhere it is withdrawn andvrecirculated to the well. The vacuum in thetank is accurately controlled by improved three way valve means whichare automatically responsive to raising and lowering of the mud level inthe bottom of the tank so that the vacuum is increased when the mudlevel falls and is decreased when it rises.

Other objects, features and advantages of the invention may becomeapparent from the following description taken in conjunction with theaccompanying drawings, wherein like characters of reference are used todesignate like parts, and wherein:

FIGURE 1 is a view, partly in side elevation and partly in longitudinalvertical section, of the mud de-gasser 0f the invention;

FIGURE 2 is a fragmentary cross-sectional view, taken substantially inthe plane of the line 22 in FIGURE 1;

FIGURES 3 and 4 are diagrammatic illustrations of the vacuum controllingoperation of the invention.

Patented Jan. 16, 1968 Referring now to the accompanying drawings indetail, the drilling mud de-gasser of the invention is illustrativelyembodied in Erwin Patent No. 2,869,673, is designated generally by thereference numeral 10 and com prises a horizontally elongated vacuum tank11 mounted by suitable supports 12, 13 on a base, platform or skid 14.The tank has an inlet end 11a, an outlet end 11b and a sloping bottomwhich slants downwardly from the inlet to the outlet end of the tank. Aremovable cover 15 is provided on the outlet end 11b so that access tothe tank interior may be had for purposes of inspection and cleanmg.

An intake pipe 16 delivers gas cut mud from the well to the tank and isprovided with a manually set throttle valve 17 so that the flow of mudinto the tank may be regulated. The intake pipe 16 extends through theinlet end 11a and communicates with a trough 18 which extendslongitudinally centrally in the upper portion of the tank for almost thefull length of the latter and is closed at the end 18' thereof.Conveniently, the trough 18 may be formed by extending the intake pipe16 into the tank and cutting away the top portion of the pipe. A pair ofdown wardly divergent cascade plates or baffle plates 19 are secured attheir upper edges to the opposite sides of the trough 18, the loweredges of these plates being suitably supported, as by pins 2.0 on theinside of the tank, thus also serving to support the trough 18 inposition.

It will be apparent that gas cut mud passing through the intake pipe 16into the trough 18 will overflow from the trough onto the baflle plates19 and will cascade over the bafile plates as indicated by the arrows 21in FIGURE 2. The interior of the tank is maintained at sub-atmosphericpressure by means hereinafter described, and the vacuum in the tankeifectively withdraws all gases from the mud as the latter cascades overthe bafile plates. The flowing mud drops off of the plates 19 onto thesides of the tank and gravitates along the sides to the bottom portionof the tank where it maintains a varying level indicated at 22. Whatevergases still remain in the mud after cascading over the plates 19 areremoved by the vacuum during gravitation of the mud along the sides ofthe tank, so that gas free mud collects on the tank bottom from where itpasses through a suitable outlet pipe 23 for recirculation to the well.Any suitable means (not shown), such as a centrifugal pump as disclosedin our patent No. 3,241,295, a positive displacement pump, or a jetstream, as disclosed in Erwin Patents Nos. 2,748,884 and 2,869,673, maybe employed for inducing the flow of mud through the tank.

Sub-atmospheric pressure in the tank is produced by a vacuum pump 24mounted on a platform 25 on top of the tank and driven by a motor 26also mounted on the platform. The crankcase of the pump 24 is preferablyprovided with a sight glass or gauge 27 to indicate the oil leveltherein. An oil reservoir 28 is mounted by suitable legs 29 On theplatform 25 and an oil supply line 30, equipped with a manual controlvalve 31, extends from the oil reservoir to the crankcase of the pump 24so that oil may be added to the crankcase as required for properlubrication.

The pump 24, of course, exhausts to the atmosphere while the intakemanifold 32 of the pump is connected to a conventional float-actuatedliquid trap 33, also mounted on the platform 25. A gas suction line 34extends from the trap 33 to a vacuum control valve 35, the latter havingpor-t means 36 open to the atmosphere and also having a suction pipe 37which extends into and communicates with the interior of the vacuumtank. Preferably, the pipe 37 passes through the removable cover 15, sothat it may be removed with the cover for inspection or cleaning.

The control valve 35 is automatically operated by a float 38 in responseto rising or falling of the mud level 3 22 in the tank. The float 38 iscarried by an arm 39 pivotally mounted as at 40 inside of the cover 15,the pivot 40 projecting to the outside of the cover and carrying a link41 which operatively engages the valve 35 in any suitable manner, itbeing understood that the valve 41 itself is of any suitableconventional construction.

As is diagrammatically shown in FIGURE 3, when the mud level 22 in thetank 11 falls because the inflow of mud is not as great as the outflow,downward movement of the float 38 actuates the valve 35 so as to placethe suction pipe 37 in direct communication with the suction line 34 ofthe pump 24, and the vacuum in the tank is increased. On the other hand,as shown in FIGURE 4, when the mud level rises, the float moves thevalve 35 to a position in which the suction pipe 37 is communicated bythe port means 36 to the atmosphere, thus permitting outside air toenter the tank and decrease the vacuum therein. Operation of the pump 24may continue under such circumstances, with the pump simply drawing airfrom the atmosphere through the port means 36 of the valve, as will beapparent.

The purpose of the aforementioned trap 33 is to prevent liquids fromentering the vacuum pump 24, the trap fulfilling this purpose bycollecting and storing the undesired liquid which may be occasionallydrained from the trap through a manual drain valve 42. If periodicdraining of the trap is overlooked, an excessive amount of liquid in thetrap will cause the float of the trap to close a valve (not shown)communicating with the suction line 34, thus preventing furtherformation of vacuum in the tank 11. In order to eliminate thisdisadvantage and to provide for automatic draining of the trap, a drainline 43 extends from the trap to the interior of the tank 11 and a checkvalve 44 is provided in the drain line, which permits liquid flow fromthe trap to the tank only. When the pump 24 is stopped, the vacuum inthe line 34 will leak off more rapidly than the vacuum in the tank, andwhen this condition arises, the greater vacuum in the tank will causeliquid accumulated in the trap to flow through the check valve 44 intothe tank, thus automatically draining the trap.

A vacuum gauge 45 is provided on the tank 11 and a similar gauge 46 isprovided on the suction line 34 for determining the relative vacuumconditions existing therein.

While in the foregoing there has been described and shown the preferredembodiment of the invention, various modifications may become apparentto those skilled in the art to which the invention relates. Accordingly,it is not desired to limit the invention to this disclosure and variousmodifications and equivalents may be resorted to, falling within thespirit and scope of the invention as claimed.

What is claimed as new is:

1. In a drilling mud tie-gassing apparatus, the combination of ahorizontally elongated vacuum tank having an inlet end and an outlet endand a sloping bottom slanting downwardly from the inlet toward theoutlet end, an intake pipe for gas cut mud extending into the inlet endof said tank, a horizontal trough extending longitudinally centrally inthe upper portion of the tank and communicating with said intake pipe,8. pair of downwardly divergent baflie plates extending from oppositesides of said trough toward the respective opposite sides of the tankwhereby mud delivered into the trough may cascade over said baflieplates and gravitate along the sides of the tank to accumulate on thesloping bottom thereof, an outlet pipe for gas free mud extending fromthe bottom portion of the tank outwardly through the outlet end thereoffor recirculation of gas free mud to a well, a vacuum pump, a suctionline extending from said pump, a three-way vacuum control valve having afirst port connected to said suction line, a second port, and port meanscommunicating with the atmosphere, a suction pipe extending from saidsecond port of said valve to the interior of said tank, a float buoyanton the level of mud in the bottom portion of the tank, and meansoperatively connecting said float to said control valve whereby thevalve may directly communicate said suction pipe to said suction lineand pump to increase the vacuum in the tank when the mud level isfalling and whereby the valve may communicate said suction pipe throughsaid port means with the atmosphere to decrease the vacuum in the tankwhen the mud level uses.

2. The apparatus as defined in claim 1 together with a liquid trapinterposed in said suction line between said control valve and saidvacuum pump, a drain pipe extending from said trap into said vacuum tankwhereby liquid collecting in the trap may be automatically drained by avacuum differential between the tank and the suction line when said pumpis inoperative, and a check valve provided in said drain pipe forpermitting flow from the trap to the tank only.

3. In a drilling mud cle-gassing apparatus, the combination of ahorizontally elongated vacuum tank having an inlet end and an outletend, an intake pipe for gas cut mud extending into the inlet end of saidtank, an outlet pipe for gas free mud extending from the bottom portionof the tank outwardly through the outlet end thereof for recirculationof gas free mud to a well, a vacuum pump, a suction line extending fromsaid pump, a three-way vacuum control valve having a first portconnected to said suction line, a second port, and port meanscommunicating with the atmosphere, a suction pipe extending from saidsecond port of said valve to the interior of said tank, a float buoyanton the level of mud in the bottom portion of the tank, and meansoperatively connecting said float to said control valve whereby thevalve may directly communicate said suction pipe to said suction lineand pump to increase the vacuum in the tank when the mud level isfalling and whereby the valve may communicate said suction pipe throughsaid port means with the atmosphere to decrease the vacuum in the tankwhen the mud level rises.

References Cited UNITED STATES PATENTS 700,068 5/1902 Morison -1701,569,105. 1/1926 West 55-192 2,779,503 1/1957 Wright et al. 55-169 X2,869,673 1/ 1959 Erwin 55-192 REUBEN FRIEDMAN, Primary Examiner.

I. ADEE, Assistant Examiner.

